Vernier friction knob



Patented July E, 1929.

U .iaTTES maan rATnn'r orifice.

HARRY L. BRADLEY, OF MILVAUKEE, "WISCONSIN, ASSIGNOR T() THE RELANGE CDMPANY, F MILWAUKEE, VISCONSIN, A CORPORATIN OIE' 'WEECGNSN.

VEB/HIER. FRIGTION KNOB.

Application filed April 29, 1925. Serial No. 26,662.

This invention relates to certain new and useful improvements .in vernier friction knobs especially adapted to revolve radio dials at an even speed slower than that possible by direct control, to thus facilitate fine tuning.

lt is a general object of this invention to simplify and improve the construction of Vernier friction knobs.

A further object of this invention iste provide an improved verni `r friction knob having a mounting' stud adapted to be lined to the panel and a knob proper adapted to be readily secured over the stud and held against accidental detachment by a friction member or rubber Washer which is adapted to be enraged with the periphery of the adjacent tuning dial.

lWith the above and other objects in view which Will appear as the description proceeds, my invention resides in the novel construction, combination and arrangement of parts substantially as hereinafter described and more particularly delined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed invention may be made as come within the scope of the claims.

ln the accompanying drawing, l have illustrated one complete example of the physical embodiment of my invention constructed according;` to the best mode l have so far devised for the practical application of the principles thereof, and in which:

Figure 'l is a perspective view of a. radio front panel and a tuninpr dial equipped with one of my improved Vernier friction knobs, the panel being broken aivay and but a portion of the dial shown, and

Figure 2 is a vievv taken through Figure l on the plane of the line 2 2, parts thereof being in section and parts in elevation.

lteferringl now more particularly to the accompanying drawing in which like numerals designate like parts. the numeral 5 designates the front panel of a radio receiving, set which may be of any character having;r one or more tuning' dials 6 rotatably mounted on the exterior thereof. The dials are connected with and control variable condensers or other parts and preferably have a beveled peripheral edge 7 provided with suitable graduations.

In tuning` a radio set, it is often desirable to move the dials 6 at an extremely slow, even speed and this is impossible Without the means of a vernici' attachment. luft-he d 'awmg, l have illustrated an improved vernier attachment 8 which is adapted to be mounted on the panel adjacent the peripheral edge of each dial so that a slonT even turning.; motion may be readily imparted to the dial.

The vernier attachment comprises a stud 9 having` a tiange l0 spaced from its inner end which forms a sleeve or collar l1 adapted to lit in an opening 13 for-med in the panel 5, the stud being secured in position by a screw 1l inserted from the rear of the panel and threaded in the bore 15 of the stud. The outer end of the stud enlarged to form a head 1 6 Which is slidable in the bore ll' of a knob 18.

The knob 18 preferably has its outer peri pheral edge 19 knurled to facilitate turniing` and its inner end is reduced and channeled, as at 20, to provide a flange 2l behind which the inwardly extending flange 22 of a friction member 23, such as a rubber Washer or the like, is engaged. rlhe inner end 2li of the friction member closes the bore of the knob and has an opening therein of a diameter to have a snugl lit about the stud shank portion and cooperate with the abrupt shoulder 25 formed at the juncture of the head and shank portion to prevent the accidental dislodgment of the knob.

As will be readily apparent, the stud 9 mounted on the panel 5 at the proper place and the knob 18 is readily pushed thereover and held in place by the friction member 23, the beveled outer end 26 of the head lli facilitating the slipping of the friction inember thereover. The inner peripheral edge of the friction member is preferably slightly beveled, as at 27 to insure a good Contact With the dial and when the friction member is formed of rubber, live rubber is preferable.

From the foregoing description taken in connection with the accomjninying` drawing, .it will be rzadily apparent to those skilled in the art to which an invention of this chau acter appertains, that l provide a very novel and improved vernier knob which is simplified to facilitate manufacture and which is very convenient of application to radio sets.

Vlhat I claim as my invention is:

l. il device of the character described, comprising,- a mounting stud, a knob rotatable on the stud, a friction member carried by the knob, and yieldable means rotatably securing the knob on the stud and permitting the ready detachment of the knob from the stud by the exertion of an outward pull thereon. y

2. 'A' device of the character described, comprising a mounting stud, a head formed on the outer end of the stud, av knob having a central bore to receive the stud head, whereby the knob is rotatably mounted on the head, and means including a friction member carried by the knob for securingthe same on the' stud, said stud head providing a broad bearing for the knob.

' 3. A device of the character described, comprising a mounting stud, a head formed .on the end of the stud, a knob having a central bore to receive the stud head and rotatably mounted thereon, a friction member carried by the knob, and cooperating means formed by the friction member and the stud head to v prevent t-he accidental dislodgment y of the knob from the stud.

' y 4. A device of the character described, comprising a mounting stud having a shank portion and an enlarged portion outwardly of the shank portion to form a head, the inner end of the head terminating in an abrupt shoulder, a knob having a central bore to receive the stud head, and a friction member secured over the inner end of the knob and having a bore of a diameter less than that of the stud head and registering with the knob central bore, whereby outwardly movement of the knob on the stud is limited by the friction member abutting the stud head shoulder.

5. A device of the character described, comprising a mounting stud, having a shank portion and an enlarged portion outwardly of the shank portion and forming a head, the inner end of the head terminating in an abrupt shoulder, a knob having a central bore of a diameter to receive the stud head,

and a friction member of yieldable material secured over the inner end of the knob and having a'bore of a diameter less than that of the Stud head and registering with the knob central bore, whereby the knob may be pushed over the stud head and held in place on the stud by the friction member abutting the head shoulder, said shoulder dctning the outward limit of movement of the knob.

In testimony whereof I aix my signature.

HARRY L. BRADLEY. 

